|
Hazards & Hazardous Materials (Continued)
<br />o Additional dust control measures may be identified and implemented by contractors, as necessary,
<br />especially if dry and windy conditions persist during periods of earthwork.
<br />o Compliance with all Bay Area Air Quality Management District rules and regulations.
<br />Vertical and Horizontal Preferential Pathways: If development plans include the construction of deep
<br />foundations, the foundation of the buildings shall incorporate measures to help reduce the potential for the
<br />downward migration of contaminated groundwater. These measures shall be identified in -the site-specific
<br />geotechnical investigation reports. Appropriate measures shall be implemented to reduce vapor migration
<br />through trench backfill and utility conduits. Such measures may include placement of low -permeability backfill
<br />"plugs" at intervals on-site and where utilities extend off current parcel boundaries.
<br />• Storm Water Pollution Controls: A storm water pollution prevention plan (SWPPP) will be required to be
<br />prepared for the site. Storm water pollution controls shall be based on best management practices (BMPs), such
<br />as those described in "Guidelines for Construction Projects" and "Erosion and Sediment Control Field Manual"
<br />published by the San Francisco Regional Water Quality Control Board.
<br />• Excavation De -Watering: Although not anticipated, if excavation de -watering is required, the water will be
<br />sampled and analyzed prior to pumping to evaluate discharge alternatives. The developer's environmental
<br />consultant shall collect a sample of the water for laboratory analyses for COPCs; other analyses may be
<br />required, based on the intended use of the water.
<br />Additional Soil Management Protocols During Construction Activities: Soil with residual COPCs may be
<br />present on-site. Subsurface investigations planned for the Sites will determine the presence or absence of COPCs
<br />in soils. Once soils are tested, a Site specific soil management plan (SMP) will be prepared. At the present time,
<br />there are no known chemical source areas or areas of soil contamination on either Site. The protocols to be
<br />followed in the event that unknown areas of contamination are identified during development are described in
<br />this section.
<br />• Procedures for Discovery of Unknown Areas of Contamination: Site development activities may result in the
<br />identification of previously unknown areas or types of contamination. Unknown conditions which may trigger
<br />contingency monitoring procedures during site development include, but are not limited to, the following:
<br />o Oily, shiny, or chemical saturated soils;
<br />o Soil with a significant chemical or hydrocarbon -like odor; or
<br />o Significantly discolored soils.
<br />Upon the discovery of one of the conditions identified above, the contractor will conduct the contingency
<br />monitoring. Contingency monitoring, if conducted, will consist of the following steps: If unknown areas of
<br />potential discolored soils are encountered, additional analyses should be conducted for the suspected constituents
<br />to assess the actual composition of the suspected contamination. A State environmental regulatory agency
<br />should be contacted for assistance in determining if additional sampling and potential mitigation is necessary. If
<br />the encountered materials are suspected to contain volatile organic chemicals, the following contingency
<br />monitoring procedures may be followed:
<br />Conduct contingency monitoring by taking organic vapor readings using an organic vapor meter (OVM) or an
<br />organic vapor analyzer (OVA) to screen for the presence of fuel, oil, or solvents. If the OVM/OVA indicates that
<br />an unknown area of fuel, oil, or solvents has been detected, then a State environmental regulatory agency should
<br />be notified to determine if additional sampling is appropriate prior to continuing construction in that area.
<br />OVM or equivalent screening methods will be conducted by experienced personnel only.
<br />If an unknown area of soil contamination has been identified, and the State environmental regulatory agency
<br />requests additional characterization, the following steps will be taken: Soil samples will be collected from the
<br />identified area and analyzed for the likely COPC. depending on the suspected type of contamination. The
<br />at San Leandro Crossings Initial Study 19 March 2009
<br />POTENTIALLY
<br />ISSUES
<br />POTENTIALLY
<br />SIGNIFICANT
<br />LESS THAN
<br />NO
<br />SIGNIFICANT
<br />UNLESS
<br />SIGNIFICANT
<br />IMPACT
<br />SOURCES
<br />ISSUES
<br />MITIGATION
<br />IMPACT
<br />INCORPORATED
<br />Hazards & Hazardous Materials (Continued)
<br />o Additional dust control measures may be identified and implemented by contractors, as necessary,
<br />especially if dry and windy conditions persist during periods of earthwork.
<br />o Compliance with all Bay Area Air Quality Management District rules and regulations.
<br />Vertical and Horizontal Preferential Pathways: If development plans include the construction of deep
<br />foundations, the foundation of the buildings shall incorporate measures to help reduce the potential for the
<br />downward migration of contaminated groundwater. These measures shall be identified in -the site-specific
<br />geotechnical investigation reports. Appropriate measures shall be implemented to reduce vapor migration
<br />through trench backfill and utility conduits. Such measures may include placement of low -permeability backfill
<br />"plugs" at intervals on-site and where utilities extend off current parcel boundaries.
<br />• Storm Water Pollution Controls: A storm water pollution prevention plan (SWPPP) will be required to be
<br />prepared for the site. Storm water pollution controls shall be based on best management practices (BMPs), such
<br />as those described in "Guidelines for Construction Projects" and "Erosion and Sediment Control Field Manual"
<br />published by the San Francisco Regional Water Quality Control Board.
<br />• Excavation De -Watering: Although not anticipated, if excavation de -watering is required, the water will be
<br />sampled and analyzed prior to pumping to evaluate discharge alternatives. The developer's environmental
<br />consultant shall collect a sample of the water for laboratory analyses for COPCs; other analyses may be
<br />required, based on the intended use of the water.
<br />Additional Soil Management Protocols During Construction Activities: Soil with residual COPCs may be
<br />present on-site. Subsurface investigations planned for the Sites will determine the presence or absence of COPCs
<br />in soils. Once soils are tested, a Site specific soil management plan (SMP) will be prepared. At the present time,
<br />there are no known chemical source areas or areas of soil contamination on either Site. The protocols to be
<br />followed in the event that unknown areas of contamination are identified during development are described in
<br />this section.
<br />• Procedures for Discovery of Unknown Areas of Contamination: Site development activities may result in the
<br />identification of previously unknown areas or types of contamination. Unknown conditions which may trigger
<br />contingency monitoring procedures during site development include, but are not limited to, the following:
<br />o Oily, shiny, or chemical saturated soils;
<br />o Soil with a significant chemical or hydrocarbon -like odor; or
<br />o Significantly discolored soils.
<br />Upon the discovery of one of the conditions identified above, the contractor will conduct the contingency
<br />monitoring. Contingency monitoring, if conducted, will consist of the following steps: If unknown areas of
<br />potential discolored soils are encountered, additional analyses should be conducted for the suspected constituents
<br />to assess the actual composition of the suspected contamination. A State environmental regulatory agency
<br />should be contacted for assistance in determining if additional sampling and potential mitigation is necessary. If
<br />the encountered materials are suspected to contain volatile organic chemicals, the following contingency
<br />monitoring procedures may be followed:
<br />Conduct contingency monitoring by taking organic vapor readings using an organic vapor meter (OVM) or an
<br />organic vapor analyzer (OVA) to screen for the presence of fuel, oil, or solvents. If the OVM/OVA indicates that
<br />an unknown area of fuel, oil, or solvents has been detected, then a State environmental regulatory agency should
<br />be notified to determine if additional sampling is appropriate prior to continuing construction in that area.
<br />OVM or equivalent screening methods will be conducted by experienced personnel only.
<br />If an unknown area of soil contamination has been identified, and the State environmental regulatory agency
<br />requests additional characterization, the following steps will be taken: Soil samples will be collected from the
<br />identified area and analyzed for the likely COPC. depending on the suspected type of contamination. The
<br />at San Leandro Crossings Initial Study 19 March 2009
<br />
|